In the past, in situ attempts to prepare liquid mixtures that consist of a dilutable fluid concentrate and a suitable diluting liquid, in predetermined volumetric ratios, have often resulted either in waste of the concentrate or in an other-than-desired amount of concentrate in the mixture.
Consider, for example, a portable 5-gallon bucket, of the type often used by a janitor or other service person to clean a floor. The service person may combine a dilutable liquid concentrate such as a concentrated soap solution with tap water in the bucket to produce a soapy mixture. It is well known, however, that proper dilution directions, even if made available, are not always followed. Accordingly, if the concentration of soap solution in the mixture is so low as to render the mixture ineffective for purposes of removing dirt from the floor, or if the concentration of soap solution in the mixture is so high as to produce streaking on the floor, the result in both instances is clearly undesirable. Furthermore, spillage of the concentrated soap solution on the floor, obviously resulting in waste, may further result in damage to the floor, which is also a clearly undesirable result.
Mixtures containing other-than-desired concentrate levels occur for a variety of reasons, many of which involve error in human judgment. It would be desirable, therefore, to greatly reduce--or even better to totally eliminate--the probability of human error in this regard.